In operation of an internal combustion engine, blow-by gasses are generated in the crankcase. These blow-by gasses comprise an oil-air mixture. From this mixture the oil is to be separated and collected while the air is to be supplied to an intake manifold of the internal combustion engine.
For example, DE 10 2009 035 742 A1 describes an oil separating device for a crankcase of an internal combustion engine. The known separating device comprises a tubular inner part and an outer part surrounding it. The outer part has a baffle wall. The gas jets existing from gas passages in the interior part impinge on this baffle wall. A spherical valve element controls the volume flow that is impinging on the baffle wall. The oil that is separated at the baffle plate is collected while the air is supplied to the intake manifold of an internal combustion engine.